To provide a method for regenerating an inorganic solid treating agent by fixing halogen, the capacity of which agent for isomerizing a non-conjugated carbon-carbon double bond of an organic compound is increased and which agent contains a component shown by compositional formula: Al_2O_3. ハロゲンを固定化することにより有機化合物の非共役炭素−炭素二重結合に対する異性化能が増大した組成式Al_2O_3で表わされる成分を含む無機固体処理剤の再生方法 - 特許庁